The Forsyth Institute affiliated with Harvard University is the world's preeminent organization dedicated to research and training in the areas of oral and craniofacial science. Teeth and the bony structures to which they are connected are central to most aspects of dental research. The three-dimensional x-ray data generated by microCT and the associated analyses provide the most quantitative, accurate, and efficient method to measure pathological and developmental changes in bones and teeth. The lack of easy access to microCt analyses has been an impediment to many researchers at Forsyth, resulting in reliance on long- distance collaborations or alternative methods to quantify these hard tissue changes. Thus, there is a strong need for convenient and inexpensive access to microCT analysis of bone and tooth samples by Forsyth researchers. The goal of this proposal is to meet this need by acquiring in house ex-vivo microCT capability. 66% of the PIs at Forsyth plan to use this instrument, attesting to the importance of mineralized tissue analyses at Forsyth. The Scanco 50 micro computed tomography (Scanco 50 microCT) instrument will enable more precise and comprehensive observations of the many significant projects that are ongoing at Forsyth (i.e. improved analysis of mutant mouse bone tissue) and provide investigators at Forsyth with the opportunity to easily and cost-effectively use this important technology in their research programs. Other microCT systems in the Boston area are either unavailable to our investigators or have reached maximum capacity. A total of 18 investigators are participating in this project. 12 investigators with 14 active NIH- funded Projects and current year direct grant awards will benefit from this proposed microCT shared Instrument grant (SIG). The participants in this application represent 62% of the NIH-funded projects in the Institute. Other Forsyth employees and neighboring scientists will also benefit. The proposed ex vivo microCT instrument will greatly expand and improve existing and pending NIH-supported projects, and it will address future needs created by the planned expansion of our research programs as dictated by our Strategic Plan. The Principal Investigator and Co-PIs have extensive experience with microCT scanners and will provide leadership and assistance for instrument's proper use. A Research Oversight Committee will provide overall direction and guidance. The Forsyth Institute is fully committed to support the proposal.